Karim Benzema and Cristiano Ronaldo arrived at the Bernabeu in the same summer. It was 2009, and while they, or we, didn't know it at the time, so much of the French striker's career would be tied up in how Ronaldo performed.

As Ronaldo evolves and changes as a player, Benzema must go with the flow of that and accept that much of what Ronaldo does is a direct reflection of his role.

Benzema is arguably one of the most divisive strikers in the world, and for many, he is an acquired taste. You're either in or out, you either get it or you don't, and Ronaldo certainly understood his importance -- and Real Madrid too. But Ronaldo's recent form has exposed Benzema's weaknesses and his inability to lead a team into battle. Real Madrid need a dangerous striker, and they need one soon.

Benzema has seen off challenges for his position before -- Javier Hernandez came and went, as did Emmanuel Adebayor and so did Mariano. Some were brought in as backups, as "B options" or simply to create competition and depth. Benzema has survived the longest with Real Madrid not spending any significant amount of money on a No. 9 in almost a decade.

Alvaro Morata was sold and brought back from Juventus, but he was seen as a player who didn't complement Ronaldo and was sent to the highest bidder last summer. That word "complement" has been used so many times to describe Benzema that he has rarely been assessed on his own. His success has always been viewed through the lens of what Ronaldo was doing. His place in the side was defined, and defended, for so long based on his overall effectiveness. And for so long, it worked.

It has caused Real Madrid to neglect the centre-forward position and the importance of it. That should and will change this summer as Ronaldo's strike rate drops and Benzema's weaknesses become ever more apparent. By definition, strikers, well, they are quite simply expected to score goals, but the divisive Benzema has always been packaged and sold as something different.

Cristiano Ronaldo Karim Benzema woe Alex Caparros/Getty Images

Just twice in his nine-year career has Benzema been as inefficient in front of goal in the first half of the season as he has in this one. He has scored just twice in the league. Not since Jose Mourinho was on the bench has the Frenchman been so ineffective.

There are simply too many world-class No. 9s that could possibly be on the market this summer for Real Madrid not to invest in a new one, and it has been too long. For years, regardless of Benzema's strike rate, his work off the ball and ability to create room for his teammates was touted as the reason for him keeping his place. And it was true. It's amazing what kind of holes a 60-goal-a-year Ronaldo could mask.

But now, with Ronaldo misfiring and Real Madrid stumbling, the Frenchman's lack of goals is becoming glaringly obvious.

Mauro Icardi, who has scored 18 goals in 22 games, along with Harry Kane, who has landed 22 goals in 25 games, have been named as possible new arrivals. One gets the feeling that Robert Lewandowski might be willing to listen to offers too.

The collateral damage around Benzema's fall from grace has been brutal too. Isco is the latest linked with a move away, as Real players grow tired of their inability to score at will. The reports of Isco leaving Madrid might have seemed harmless at the time, but if he leaves, it is an important juncture for Real Madrid.

And a lot can be gleaned from whether Isco or Benzema stay this summer.

We could be about to see Real Madrid's first outlay on a No. 9 since Benzema's arrival and in reality, despite his protests, he has little to complain about. Either keeping or selling Benzema represents something far more important too. If he stays, it's a suggestion that Ronaldo remains the main man, but if Benzema is sold and a player, like Kane for example, is brought in, it suggests the side is moving away from the Ronaldo era. So Benzema's future will be telling as to Madrid's plans going forward, as well.